Table of Contents
What device reads the codes and allows you to hear a CD?
The CD player has the job of finding and reading the data stored as bumps on the CD. Considering how small the bumps are, the CD player is an exceptionally precise piece of equipment.
What device runs a CD?
A CD player is an electronic device that plays audio compact discs, which are a digital optical disc data storage format. CD players were first sold to consumers in 1982.
How are CDS coded?
The information on a CD is encoded in a much more subtle way that uses complex and clever data encoding techniques, including eight-to-fourteen modulation (EFM) and non-return to zero inverted (NRZI) coding. Artwork: How pits and lands encode zeros and ones on a CD’s surface.
What technology does a CD use?
A CD works by focusing a 780 nanometer wavelength semiconductor laser onto a single track of the disc. As the disc rotates, the laser beam measures differences in the way light is reflected off the polycarbonate layer on the bottom of the disc, converting it to sound.
How does a CD-R disc work on a computer?
Normal CDs can not be modified — they are read-only devices. A CD-R disc needs to allow the drive to write data onto the disc. For a CD-R disk to work, there must be a way for a laser to create a non-reflective area on the disc. A CD-R disc therefore has an extra layer that the laser can modify.
How does a CD read from a CD?
The CD drive shines a laser at the surface of the CD and can detect the reflective areas and the bumps by the amount of laser light they reflect. The drive converts the reflections into 1s and 0s to read digital data from the disc. See How CDs Work for more information. Normal CDs can not be modified — they are read-only devices.
How does the tracking work on a CD player?
What the CD Player Does: Tracking The hardest part is keeping the laser beam centered on the data track. This centering is the job of the tracking system. The tracking system, as it plays the CD, has to continually move the laser outward.
What kind of data can be stored on a CD?
There are several different formats used to store data on a CD, some widely used and some long-forgotten. The two most common are CD-DA (audio) and CD-ROM (computer data). For more information on CDs and related topics, check out the links on the next page.